Increasing the correct connection of car battery jumper cables with an enhanced tag warning

Every year people are injured while improperly 'jump starting' automobiles using battery booster cables. The most common scenario leading to injury occurs when people attach both negative leads to the battery terminals instead of properly grounding the negative lead of the 'dead' battery to that vehicle's engine block. The incorrect configuration can cause the 'dead' battery to explode, discharging strong sulfuric acid. Two experiments examined the effectiveness of a pictorial tag warning illustrating the hazards and the proper connection procedure. Experiment 1, using pictures of cars with open hoods, showed that participants were significantly more likely to draw the correct sequence of connections when the warning was present than when it was absent. Experiment 2, using actual booster cables to connect two realistic appearing, but fake, batteries in adjacently parked vehicles, showed that the presence of an enhanced warning on the cables significantly increased connection accuracy compared to an unenhanced warning or no warning. Together these studies show that well-designed warnings can correct inaccurate beliefs and facilitate safe behavior.